Scientists in working in Western Greenland have found evidence of an asteroid or comet impact early in the Earth’s history. At three billion years old, the crater is a billion years older than the previously oldest known crater.

Large parts of Africa’s savannas may well be forests by 2100. The study suggests that fertilization by atmospheric carbon dioxide is forcing increases in tree cover throughout Africa. A switch from savanna to forest occurs once a critical threshold of carbon dioxide concentration is exceeded, yet each site has its own critical threshold. The implication is that each savanna will switch at different points in time, thereby reducing the risk that a synchronous shock to the earth system will emanate from savannas.

Using studies that span the last three decades, scientists have compiled the first evidence-based comprehensive study of the potential for tsunamis in Northwestern California.